Kinetic Modelling of the Fenton-Like Oxidation of Maleic Acid Using a Heterogeneous Modified Polyacrylonitrile (Pan) Catalyst

Abstract

A kinetic model has been developed that expresses the oxidation of maleic acid in solution using a novel modified (polyacrylonitrile) PAN catalyst=hydrogen peroxide system. The novel modified PAN catalyst contains immobilised Fe 3 þ and its reaction with hydrogen peroxide is thought to generate reactive hydroxyl radicals according to Fenton's reaction as well as another active iron oxo species. The model takes into account the presence of both hydroxyl radicals and active iron oxo species as well as hydroperoxyl radical and hydrogen peroxide in the oxidation process. Kinetic constants for the modified PAN=H 2 O 2 system towards the decomposition of maleic acid were determined, and their sensitivity analysed. Predicted concentration profiles of the radical species ( ? OH, HO ? 2 , O ? À 2 ), as well as iron species (Fe(III), Fe(II) and FeO) helped in gaining a better understanding the oxidation process. This model, with the new set of kinetic parameters, provides a superior fit to the experimental data compared to kinetic constants from the literature.

Synthesis of Two Mononuclear Schiff Base Metal (M = Fe, Cu) Complexes: MOF Structure, Dye Degradation, H2O2 Sensing, and DNA Binding Property

“…The possible reaction mechanism of H 2 O 2 decomposition by complex 1 is given below.In the possible proposed reaction mechanism, eq 5 was an intermediate of the decomposition of H 2 O 2 by complex 1 . 57…”

Electrochemical Treatment of Wastewater by ElectroFenton, Photo‐ElectroFenton, Pressurized‐ElectroFenton and Pressurized Photo ElectroFenton: A First Comparison of these Innovative Routes

“…Indeed, it has been previously shown that EF is the least effective electrochemical process (compared with direct anodic oxidation at BDD or indirect oxidation by electro-generated active chlorine) for the removal of AO7 because of the formation of recalcitrant by-products. [42] According to the literature, the main relevant by-products are hydroquinone, oxalic and maleic acids which remain in the solution for very long times during EF process. [19,42]…”

Regeneration of a deactivated surface functionalised polyacrylonitrile supported Fenton catalyst for use in wastewater treatment

“…One of the materials successfully used is a surface functionalised nanocoated modied polyacrylonitrile (MPAN) bre in the form of a mesh. [3][4][5][6] The PAN mesh was modied to introduce surface functionalisation by amidoximation with a mixture of hydrazine and hydroxylamine at alkaline pH to allow surface complexation with iron(III) sulphate salt. 3,[7][8][9] This introduces groups such as amidoxime, amidrazone, amide and carboxylate onto the bres of the PAN mesh.…”

“…When used with hydrogen peroxide at pH 3, the catalyst is seen to give excellent oxidation of organic pollutants in wastewater. [3][4][5][6] The catalyst degrades pollutants via a heterogeneous Fentonlike mechanism (eqn (1) and (2)), which is known to be slightly slower in comparison to a homogenous Fenton's degradation. However, as the iron in this study is chelated to a PAN support, the amount of iron leaching and hence secondary pollution is reduced drastically.…”